A closely watched Canadian study is using genetically enhanced stem cells to repair damaged muscle in heart attack survivors.

Robert Clark, 67, photographed in his Toronto apartment with his cat Geisha who he credits with saving his life after a heart attack. Clark is Toronto's first patient to enter a groundbreaking cell therapy trial led by researchers at St. Michael’s Hospital and the Ottawa Hospital Research Institute. In a world first, the Canadian study uses genetically-enhanced stem cells to repair damaged muscle in heart attack survivors.

Nurses called him a celebrity, but Robert Clark said, “Nah.” He wasn’t interested in fame or anticipating fortune, but he gladly took the free cab ride home from the hospital.

After a severe heart attack five weeks ago, the 67-year-old has become the first Toronto patient to enter a groundbreaking cell therapy trial led by researchers at St. Michael’s Hospital and the Ottawa Hospital Research Institute.

In a world first, the Canadian study uses genetically enhanced stem cells to repair damaged muscle in heart attack survivors. The souped-up cells are the patient’s own, made young and healthy again — fountain-of-youth style — in a laboratory. Cell therapy researchers across the globe are monitoring the study, cautiously optimistic that it could lead to a breakthrough the field has long been waiting for.

“We all have, circulating in our blood, stem cells that have the potential to repair and regenerate damaged tissues. In people with risk factors for heart disease or in patients who have suffered a heart attack, these cells don’t have the same healing capacity,” says Dr. Michael Kutryk, a cardiologist at St. Michael’s and principal investigator on the study.

“The strategy we are using is to restore the body’s own mechanisms to help fix the heart.”

The trial’s first Toronto patient was having a little rest on his couch on April 28 when he started to feel “funny.”

“OK, so I was petting my cat,” Clark recalls, “and all of a sudden she went ‘meow, meow, meow,’ and jumped right on my chest, right?”

As he tells the story in his 5th-floor Upper Beach apartment, Clark gets down on his hands and knees and yanks Geisha the cat out from under a small cot. She’s a beautiful tabby with saucer eyes as bright and clear a shade of green as her owner’s are blue.

Clark is not saying the cat gave him a heart attack. Quite the opposite, actually.

“She was warning me that something was wrong,” he says solemnly, cradling Geisha in his skinny, tattoo-covered arms. (“These are older than you are,” he says of the faded green ink blots, and it’s true.)

Clark speaks with a Newfoundland accent carried over from the first nine years of his life, which he spent in Cornerbrook before his parents moved the family to Toronto in search of better job prospects.

He has worked as a plumber, a jeweller, a labourer for a steel company, a brewery worker and a janitor at Exhibition Place. His wife passed away a decade ago after a battle with cancer. He has five children and four grandchildren spread across the province — in Sudbury, North Bay, Ottawa and Hamilton.

Hiking up baggy blue jeans held up by a belt, Clark says he has lost 30 pounds since the heart attack. After Geisha jumped on his chest that day, he felt an intense bolt of pain shoot from his wrist, all the way up his left arm and into his heart. He stumbled over to the phone by his bed and dialed 911.

The heart attack caused severe damage, which made him a strong candidate for the study.

When Dr. Kutryk’s team asked him to participate, Clark thought about it for a couple of days, then gave them his answer: “I says, ‘Yeah, OK, why not? Maybe if it could help someone, fine.’”

In a procedure on May 13, cells were extracted from his blood and enhanced in a laboratory with a special gene — endothelial nitric oxide synthase — which stimulates blood vessel growth and improves tissue healing.

Clark doesn’t know if the enhanced cells were injected back into his heart, or if he was part of a control group — one that received regular stem cells, and another that got a placebo. The trial is double-blind, so even Clark’s doctors don’t know where he landed.

A heart attack happens when a major coronary artery becomes blocked and starves the heart of blood flow. If it’s blocked long enough, the heart muscle begins to die. When it dies, healthy heart muscle is replaced with inflammation and scar tissue, which can lead to serious, life-threatening problems such as arrhythmia and heart failure.

Cardiovascular diseases such as heart failure cost the Canadian economy more than $20 billion per year, according to a 2010 study by the Conference Board of Canada.

“Heart failure is a colossal problem for health care, generally, and the most common cause of heart failure, still, is one or more heart attacks,” says Dr. Warren Sherman, director of cardiac cell-based endovascular therapies at the Columbia University Medical Center.

Sherman and other cell therapy researchers around the globe have been monitoring the Ottawa-Toronto study since it launched. “It’s very innovative,” Sherman says. “Of all the studies going on for heart attack right now, this is the really one of the only ones that have deviated outside of the standard,” he says, modifying cells “in a way that may very well help to boost the levels of recovery.”

The advantage of using a patient’s own stem cells to try to repair damaged heart muscle is that it is safer and less likely to cause inflammation than using donor cells. The disadvantage is that the cells are as old as the patient and affected by the same factors that hurt the heart in the first place — diabetes, cholesterol and high blood pressure, for example. In short, they don’t have the same healing abilities as younger cells.

The Toronto and Ottawa researchers knew from other studies that old cells aren’t as effective in repairing damaged heart muscle as young cells, so they found a way to turn back the clock.

Stem cell therapy has come a long way from its overhyped beginnings, recovering from controversies prompted by the use of embryonic stem cells, the touting of unproven overseas “miracle” cures, and studies with questionable methodology that cast a pall over the whole field.

“There have been disappointments in the realm of stem cell research,” says Timothy Caulfield, a professor at the University of Alberta's Faculty of Law,
who holds the Canada Research Chair in health law and policy. “This is a phenomenally exciting area, no doubt about it, with huge potential, but there actually haven’t been that many successful clinical trials that would result in a therapy that was of relatively near-future application for the clinic.”

That’s what makes this study so exciting, Caulfield says. “It’s nice to see these very rigorous, carefully controlled trials taking place. It’s very important for the legitimacy of the field, but also for public trust ... we need data like this to demonstrate what works and doesn’t work.”

Dr. Duncan Stewart, the Ottawa-Toronto study’s lead investigator and CEO of the Ottawa Hospital Research Institute, says he believes medical research is entering a new era where, increasingly, we will see regenerative approaches — molecular and cell-based therapies — being used to restore function and reverse damage after conditions such as kidney failure, lung disease and stroke have taken their toll.

“I think if we are successful in doing this, it’s not just that we’re going to have a new therapy to help treat patients who have had large heart attacks; it will also be opening a door to using similar approaches to deal with other significant and devastating medical conditions,” Stewart says.

At home with his cat in the Upper Beach, Clark says the fear that came with not knowing whether he’d live or die is something he doesn’t want to repeat.

“It was a very scary situation, boy, I tell ya,” he says, shaking his head. “Now that I got a second chance, I just wanna take life easy, see my kids, my grandkids growing up. Stuff like that.”

Correction - June 17, 2014: This article was edited from a previous version that mistakenly said Professor Timothy Caulfield is at the University of Calgary.

More on thestar.com

We value respectful and thoughtful discussion. Readers are encouraged to flag comments that fail to meet the standards outlined in our
Community Code of Conduct.
For further information, including our legal guidelines, please see our full website
Terms and Conditions.